Account = Backbone.Model.extend({
    // having only url will cause delete to not use the id; weird
    urlRoot: '/acct',
    defaults: {
        'who': 'temp',
        'age': -1,
        'balance': -1,
    },
    initialize: function() {
        this.on('change:who', function(model) {
            var old = model.previous('who');
        });
    },
    doubleBalance: function() {
        var old = this.get('balance');
        this.set('balance', old * 2);
    },
});

Bank = Backbone.Collection.extend({
    // this has to be url and not urlRoot weird again
    url: '/acct',
    model: Account,
});
